Impossible Bosch Ebike Issue

[Bob88]

Hi Guys,

First Post here, sorry its a tech question but at my wits end. Have a Cube stereo hybrid 140 2020. After 5-10 mins of riding, a click occasionally on the downstroke. Then Bang, feels like a slipped chain, cranks take 1/4 turn to rengage. Happens under power. Happens most often pedaling out of a corner. Most attempts to make it do it on demand fail. Its intermittent.
I have so far (and in order)
1, Replaced the rear freehub body
2, Replaced the front chainring, cassette and chain with original factory spec bits.
3, Taken the whole thing to performance line bearings for a complete strip down of motor. Nothing found.
4, Replaced derailleur with upgraded GX
And still click click click click BANG.

Unsure where to go with this now. Can't sell it as broken, nobody can repair it. Any ideas?

 

[Bob88]

could be damage in the rear hub, have you tried a diffrent back wheel ?

Hi, no I have not. I only had the bike shop replace the freehub bit. However the shop said the one they removed was not actually broken. The rear wheel does not spin as freely as It did before the issue. The clicking which indicates a slip is near feels like its coming from the motor though.

My only options now are new motor or new wheel. You think wheel then?

 

[Bob88]

m8s canyon was doing the same thing but it destroyed the free hub and wheel hub but alot of ppl on here has had the same thing esp with shitmano hubs there just cheap crap.

if peter has done the motor id say it is the rear wheel hub thats the problem.

Thanks for the advice, much appreciated. Any idea of the mechanism that has actually failed if it is the rear wheel? As I said, it's unlikely to be the freehub as new. Not good with mechanics, what else is back there that could cause an issue like this?

 

[Bob88]

Stock H15 rear hub is destroyed after 4 weeks

My H15 came with no-name hubs, and in the last couple rides there's been a clunk noise coming from the hub when you start pedaling after coasting. I just got back from the bike shop who pulled apart the hub. They said the notches that the pawls sit in are "ovaling out" sending out chunks of...

www.emtbforums.com

imo you have teeth missing inside the hub what the pawl grab on to and why it is slipping.

Forgive my ignorance, so the teeth inside the hub are separate from the freehub bit I had replaced?

 

[Planemo]

Looking at shockwaves top pic, do you know if you had the whole hub replaced (everything that the spokes go into) or just the centre section (leaving the original outer hub section attached to the spokes).

I agree though, if Performance Line have had the motor apart the potential for it to still be the problem is infintessimally small.

 

[Bob88]

Looking at shockwaves top pic, do you know if you had the whole hub replaced (everything that the spokes go into) or just the centre section (leaving the original outer hub section attached to the spokes).

I agree though, if Performance Line have had the motor apart the potential for it to still be the problem is infintessimally small.

It was just the inner bit. Thanks for the help guys

 

[Bob88]

could be damage in the rear hub, have you tried a diffrent back wheel ?

OK, booked in at the shop for a new hope wheel with hope hub. Fingers crossed this solves it.

 

[Bob88]

Well, that was £278 spent on a new hope rim and hub and did absolutely nothing. The issue persists. That was the final part of the drive changed. 100% confirmed to be the motor. Anyone have the slightest clue which component would cause this? It starts as a click on the downstroke (left or right crank, it's random, but only one side clicks at a time) and then under power, skips causing a nasty bang. Then might not do it again for 5 mins. It is exacerbated by turns at speed.

 

[Bob88]

i dont know how any lbs clould not see this but there you go and why i service everything i can but if you have done any sort of millage with that free hub id say it will be toast, every time it goes bang it is taking a chunk out of the teeth or the pawls.

id just get a semi decent new wheel set like mavic e deemax

Mavic E-Deemax 30 E-MTB Wheelset | Chain Reaction

Mavic E-Deemax 30 E-MTB Wheelset - Lowest Prices and FREE shipping available from The World's largest online bike store - Chain Reaction Cycles

www.chainreactioncycles.com

Do you know if any members of this forum are familiar with the Cx internals?

 

[Planemo]

Bloody hell I feel for you, I really do.

Sorry if we were wrong on the motor given it had already been stripped and inspected but it does seem like the only culprit now.

I think Perf Line Bearings would be just as upset as you are if they identify they had missed something. Give them a call explaining all the parts you have changed and see what they say.

 

[steve_sordy]

@Bob88 You say it feels like a slipped chain. Could it actually be a slipped chain?

The only other thing I could think of, despite Performance Line's work, is a dodgy Sprag clutch in the motor.

 

[Bob88]

i thought a new hub whaould sort it but as you say it can only be the motor now that is the problem but if all the gears and motor bearings are all ok then it must be some sort of softwre problem on the controller.

id see what peter says as might have a spare motor that he could exchange for your one but depends what he has in stock or may be able to swap out the controller if he has a spare one.

i take it you have no error codes at all but this is one strange problem this motor has got as never seen it b4 and thought that new hub whould have sorted it but guess not

I had one random 503 error about 5 months ago but it's never appeared since. I think new motor is the only option, I just need to know the cause, for my sanity

 

[Bob88]

did peter change any bearings or just take a look at it? 503 is speed sensor error.

I'm sure he said he changed the bearings, or serviced them as a matter of course, but he said the motor looked fine. No issues. He said it was most likley the drive train and he rode it fairly extensively too.

 

[Bob88]

@Bob88 You say it feels like a slipped chain. Could it actually be a slipped chain?

The only other thing I could think of, despite Performance Line's work, is a dodgy Sprag clutch in the motor.

I mean I am not great mechanically but the problem persisted before and after the full change of drive components, so unlikely I would think.

 

[Zimmerframe]

@Bob88 You say it feels like a slipped chain. Could it actually be a slipped chain?

The only other thing I could think of, despite Performance Line's work, is a dodgy Sprag clutch in the motor.

I'm a bit more with Steve here.

What you're describing sounds a bit more like a slipped chain. The cranks are ultimately connected to the chainring, so if you're pedalling, even though the motor is connected, the drive should all continue as normal. Does it do it motor on and motor off ?

Is the B-Screw set correctly ?

A mate had a bike recently which was doing exactly what you're describing, but it was the chain skipping on the cassette. If you put it on a stand you couldn't replicate it. I adjusted everything and it should have been perfect then suddenly from no-where it did the same and made no sense at all.

Eventually the bike shop changed the derailleur (even though it looked completely fine) and that fixed it.

 

[Bob88]

I'm a bit more with Steve here.

What you're describing sounds a bit more like a slipped chain. The cranks are ultimately connected to the chainring, so if you're pedalling, even though the motor is connected, the drive should all continue as normal. Does it do it motor on and motor off ?

Is the B-Screw set correctly ?

A mate had a bike recently which was doing exactly what you're describing, but it was the chain skipping on the cassette. If you put it on a stand you couldn't replicate it. I adjusted everything and it should have been perfect then suddenly from no-where it did the same and made no sense at all.

Eventually the bike shop changed the derailleur (even though it looked completely fine) and that fixed it.

Definitely not the derailleur, changing it to GX did nothing. I have checked it is Definitely indexed correctly. Shifting is smooth as butter.

 

[Bob88]

can you get someone to ride with you that can see if the chain is slipping on the rear or not as not much left to check bar a bent mech hanger.

Unfortunately not an option for me but LBS did say hanger was perfect, I specifically asked them to verify during derailleur change. Peter wants the bike back to swap the motor out and investigate some more. Will update with his findings late August as am going away for a bit.

 

[Bob88]

yeah send it to peter he will sort it out as now know it is 100% the motor as everything else has been replaced.

Just by luck I managed to capture a great example of this on camera. 13 sec video. A couple of pedal strokes in a straight line, all is fine. Then I make a left hand turn, you can hear the click and then the bang as it slips.
Leisure lakes bikes denied hearing anything and caused the issue to take the bike motor out of warranty too.

 

[Slapbassmunky]

Just by luck I managed to capture a great example of this on camera. 13 sec video. A couple of pedal strokes in a straight line, all is fine. Then I make a left hand turn, you can hear the click and then the bang as it slips.
Leisure lakes bikes denied hearing anything and caused the issue to take the bike motor out of warranty too.

They didn't hear anything? It's plain as day!

So just to clarify. New drivetrain, new wheel with a hope hub, it still does it, and it's a gen 4 PL/CX motor? Do you loose power when it slips, or do you stop pedalling so the power drops off?

If the motor is making a sound like that I'd expect there would be visible wear or marks on the shaft surfaces for the one way bearings or visibly knackered sprag teeth. It certainly wouldn't last that long and someone with an expert eye would pick up on it immediately.

Have you checked all the frame pivots, and motor mount fixings? I mean properly driven the collars out and had a look at the bearings etc? If you're sure everything else is good and everything else has been checked it's where I'd be looking.

 

[ReinerSt0ff77]

Sliping Chain on the longest Gear,had some Cubes with 12 Drivetrain,change the smallest Cog 10.

 

[Bob88]

Further update, went back to performance line bearings and Peter swapped the motor out. Noise gone, no click, no slipping. He's lending me the motor so I can enjoy my summer riding planned. What a great guy. He says it's an issue He's never seen before so he is going to strip it to bits to find out the cause. Then I will either buy this motor or take the fixed one back. Either way, I am now riding!

 

[Planemo]

Brilliant news mate. Its a shame you swopped out so many parts that may needn't have been changed, but sometimes its simply a case of shit happens. At least you are back riding and I guess much of what you swopped could be considered an upgrade/servicable item anyway. Ride on!

 

[Zimmerframe]

At least it's with someone knowledgeable, experienced, professional - who's also sharing in the community, so your hardship leads to more knowledge for everyone else in the long-term.

 

[Bob88]

Brilliant news mate. Its a shame you swopped out so many parts that may needn't have been changed, but sometimes its simply a case of shit happens. At least you are back riding and I guess much of what you swopped could be considered an upgrade/servicable item anyway. Ride on!

Yeah it was all upgrades anyway. The hope hub and wheel is so nice I'm going back for the front one....